1. Combine first 5 ingredients, stirring with a whisk. Refrigerate until well chilled (at least 8 hours, or overnight).

2. Pour mixture into freezer can of an ice cream maker, and freeze according to the manufacturer’s instructions. Stir 1/3 cup of graham cracker crumbs into the finished ice cream. Spoon ice cream into a freezer-safe container; cover and freeze for 1 hour or until firm. Sprinkle each serving with 1 teaspoon graham crackers. Garnish with lime wedges, if desired.